Police said Monday they came under fire as they rushed into a housing estate in the French city of Marseille after residents alerted them that hooded people had shot "Kalashnikovs" in the air.
The outbreak of violence in La Castellane, an estate known as a drug trafficking hotspot, came just hours before Prime Minister Manuel Valls visited the southern port city to hail the progress made in fighting crime.
It was not clear what sparked the violence at a time of high jitters following the Paris attacks last month, but Marseille is known for rampant gang-related gun crime that has even prompted calls for the army to be sent in to tough neighbourhoods.
Interior Minister Bernard Cazeneuve told reporters that police recovered seven Kalashnikovs and "several" kilogrammes of drugs.
In a speech to security forces on his visit, Valls said the shots, which left no one hurt, were "unacceptable" and said the push to reduce crime was a "long-term struggle."
According to a source close to the case, residents in the housing estate -- where a 25-year-old was shot dead last month in a settling of scores -- alerted police earlier Monday that "five to ten" hooded people had fired "Kalashnikovs" in the air.
Police rushed to the scene to deal with the situation, and on their arrival, they were shot at while still in their cars, said local public security director Pierre-Marie Bourniquel.
Children at a creche in the 7,000-strong estate, where football star Zinedine Zidane famously grew up, were moved to a neighbouring school.
Security forces were still hunting for those who fired the Kalashnikovs, and riot police will deploy in the estate over the next few days, Bourniquel said.
- Easy availability of Kalashnikovs -
Police say much of the violence in Marseille is linked to turf wars between multiple rival gangs battling for control of the drugs trade in the city's poorest neighbourhoods.
The violence, they say, is made worse by the easy availability of high-calibre weapons, with Kalashnikov automatic rifles being the murder instrument of choice.
In 2013, Valls, who was then interior minister, had warned that entire neighbourhoods were "lost to the dealers."
Ironically, he visited the city Monday to pay tribute to the "excellent" results of measures taken over more than two years to fight crime.
In an interview with regional daily La Provence, Valls said crime in the city had tumbled, pointing to a 30-percent drop in armed robberies over two years and a 20-percent fall in physical violence against people.
Marseille has been a Mediterranean trading hub since antiquity and has long had a reputation as a hotbed of crime.
In the 19th century, the level of registered offences was three times higher there than in any other French city and there have been regular outbursts of gang violence ever since.
Drugs-related crime is also not new, with the city's central role in the international heroin trade famously portrayed in the 1971 film "The French Connection".
That trade was controlled by powerful international syndicates and the heroin passing through Marseille was largely destined for other markets.
In contrast, the current violence is seen as the product of a free-for-all in the supply of marijuana and related soft drugs to the local market.